JP5280081B2 - Hoisting machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a winch that utilizes energy without waste by storing a regenerative electric power during lowering operation of a hoisting/lowering electric motor in a capacitor while returning the regenerative electric power to a commercial AC power supply, and a regenerative electric power processing method for the winch. <P>SOLUTION: The winch includes an inverter 11, a hoisting/lowering electric motor 12, a controller 13, a capacitor 23, a power supply switch (electromagnetic switches 18, 19), and a charging detector 27. The controller 13 includes a function that connects the hoisting/lowering electric motor 12 to the inverter 11 via the power supply switch on the condition that the charging detector 27 detects non-charging of the capacitor 23 during lowering operation in order to store the regenerative electric power in the capacitor 23 and connects the hoisting/lowering electric motor 12 to a commercial AC power supply 10 via the power supply switch on the condition that the full charging of the capacitor 23 is detected in order to supply the regenerative electric power to the commercial AC power supply 10. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

The present invention relates to an electrical rope hoist and electric chain block hoist or the like wound vertical motion motor is driven by the driving power from the inverter.

  In a hoisting machine that includes an inverter as described above and drives the hoisting and lowering motor by the output of the inverter, the hoisting and lowering motor generates regenerative energy (regenerative power) during the lowering operation. As a method of processing the regenerative energy and applying regenerative braking to the hoisting and lowering motor, a method of supplying regenerative electric power (regenerative current) to the braking resistor and converting it into heat energy has been conventionally performed. This method requires measures against a large amount of heat generated from the braking resistor. When the capacity of the hoisting and lowering motor is large, a large capacity braking resistor is required if the hoisting and lowering operation is performed frequently. There is a problem that it is difficult to take measures against heat, such as effectively radiating generated heat. Further, by dissipating heat instead of heat energy, energy is wasted.

  As a method that does not use the braking resistor, there is a method in which a regenerative converter is provided, and regenerative power generated by the hoisting and lowering motor during the winding operation is converted into power frequency power by the regenerative converter and returned to the power supply side. This method does not require a braking resistance and saves energy. However, there are problems that the regenerative converter has a large shape and high cost (more than twice that of the inverter).

Also, as shown in Patent Document 1, when the hoisting machine descends, the hoisting and lowering motor is connected to the inverter side, and is driven to rotate by the inverter. When the rotational speed reaches a rated speed corresponding to the frequency of the commercial AC power supply, In some cases, a hoisting / lowering motor is connected to a commercial power source and the hoisting / lowering motor is operated by a commercial AC power source. Further, as shown in Patent Document 2, a capacitor is connected to the DC part of the inverter, the regenerative power during the lowering operation of the hoisting and lowering motor is stored, and the stored electric power is supplied to the hoisting and lowering motor during the hoisting operation. There is also something like that.
JP 2000-175472 A JP 2007-267504 A

  The hoisting machine described in the above cited reference 1 does not require braking resistance, does not require heat generation countermeasures, can be reduced in cost, and returns the regenerative power generated by the hoisting and lowering motor to the commercial AC power source during the hoisting operation. Although there is an advantage that it can be performed, there is a problem that it is not possible to perform a slow stop, which is a feature of the inverter-driven hoisting machine. The thing described in the cited document 2 has a problem that it is necessary to set the capacitor capacity to the maximum load × the maximum head, a capacitor having a large capacity is required, the cost is high, and the size of the apparatus is increased.

The present invention has been made in view of the above-described points, and by using the combination of storing the regenerative power during the lowering operation of the hoisting and lowering motor in the capacitor and returning it to the commercial AC power source, the size of the apparatus can be reduced. An object is to provide a hoisting machine that can use energy without waste.

In order to solve the above problems, the present invention includes a commercial AC power supply, an inverter, a winding up / down motor, and a control device, and controls the inverter under the control of the control device, and activates the winding up / down motor to perform the winding up / down operation. In a hoisting machine, a capacitor, a power supply switching device, a charge detector, and a phase detector that detects the phase of a commercial AC power supply are provided, and the inverter has a function of outputting a phase signal indicating the phase of the output. And the control device connects the winding up / down motor to the inverter via the power switch on the condition that the charge detector detects uncharged capacitor during the winding operation, and the winding up / down motor The electric power to be generated is charged in the capacitor, and the winding up / down motor is connected to the commercial AC power source via the power switch on the condition that the charge detector detects the full charge of the capacitor, and the winding up / down electric motor Transmits the power generated by the inverter to the commercial AC power source, and the inverter charges the power charged to the capacitor on the condition that the charging power of the capacitor detected by the charge detector during winding operation is not completely discharged or less than a predetermined amount. The power from the commercial AC power source is supplied via the power switch on condition that the charging power of the capacitor detected by the charge detector is completely discharged or less than a predetermined amount. A function to supply the motor for hoisting and lowering, and an acceleration hoisting operation that accelerates at a predetermined acceleration from the start of the hoisting operation to the high-speed hoisting operation at the frequency of the commercial AC power source by an inverter output during the hoisting operation, a function for decelerating winding under operation for decelerating at a predetermined deceleration from the inverter and the output peripheral when the inverter output frequency when under high speed winding operation reaches the frequency at the time under high speed winding operation The number operated by shifting a predetermined amount than the frequency of the commercial AC power source, by the phase signal from the phase signal and the inverter detected by the phase detector, when an inverter output and the commercial AC power source is synchronized, via a power switching unit When switching the motor for hoisting and lowering from the inverter to the commercial AC power supply and shifting from high speed lowering operation to decelerating lowering operation, if the inverter output frequency reaches the frequency during high speed lowering operation, the inverter is set to the output frequency. It was operated shifted by a predetermined amount than the frequency of the commercial AC power source, by the phase signal from the phase signal and the inverter detected by the phase detector, when an inverter output and the commercial AC power source are synchronized, the winding up-and-down motor power And a switching function for switching from a commercial AC power source to an inverter via a power source switching device.

  As described above, the electric power generated by the hoisting / lowering motor is charged to the capacitor under the condition that the capacitor is not charged (not fully charged) during the winding operation, and is wound under the condition that the capacitor is fully charged. The electric power generated by the vertical motor is transmitted to the commercial AC power supply, and the electric power charged in the capacitor is used for the vertical movement under the condition that the complete discharge of the capacitor or the charging power is not detected below the predetermined amount during the winding operation. Since the electric power from the commercial AC power source is supplied to the hoisting and lowering motor on condition that the capacitor is completely discharged or the charging power is equal to or less than a predetermined amount, the hoisting and lowering motor is supplied during the lowering operation. The regenerative power to be generated can be used effectively without wasting it.

Further, the switching function of the control apparatus, when it becomes a high speed winding under operation through the accelerating winding under operation at the time of winding under operation, if there capacitors fully charged, a predetermined amount than a frequency that the output frequency of the commercial AC power supply an inverter When the inverter output and the commercial AC power supply are synchronized by the phase signal detected by the phase detector and the phase signal from the inverter, the power of the hoisting and lowering motor is supplied via the power switch. Switch from the inverter to commercial AC power. In addition, when shifting from high-speed lowering operation to decelerating lowering operation, the inverter is operated with its output frequency shifted by a predetermined amount from the frequency of the commercial AC power source , and the phase signal detected by the phase detector and the inverter When the inverter output and the commercial AC power supply are synchronized by the phase signal from, the power supply of the hoisting and lowering motor is switched from the commercial AC power supply to the inverter. Thereby, the regenerative electric power generated by the hoisting and lowering motor during the lowering operation can be used effectively without wasting it. Further, with a very simple configuration, when the hoisting / lowering motor is switched from the inverter output to the commercial AC power source and from the commercial AC power source to the inverter, the hoisting / lowering motor can be smoothly switched without giving an impact.

The present invention also includes a commercial AC power source, an inverter, a hoisting and lowering motor, and a control device, and controls the inverter under the control of the control device, and activates the hoisting and lowering motor to perform the hoisting and lowering operation. In this circuit, a capacitor, a power switch, a charge detector, and a phase detector for detecting the phase of the commercial AC power supply are provided. The inverter receives the phase signal detected by the phase detector, Synchronize with the AC power supply and output a synchronization completion signal to the control device when the synchronization is completed.The control device is provided on the condition that the charge detector detects that the capacitor has not been charged during the lowering operation. The motor is connected to the inverter via the power switch, and the capacitor is charged with the electric power generated by the motor for winding and winding, and the charge detector detects that the capacitor is fully charged. The lower motor is connected to a commercial AC power source via a power switch, and the electric power generated by the hoisting / lowering motor is transmitted to the commercial AC power source, so that the charging power of the capacitor detected by the charge detector during the hoisting operation is completed. The electric power charged in the capacitor is supplied to the hoisting and lowering motor via the inverter on the condition that the electric discharge is not discharged or less than the predetermined amount, and the charging power of the capacitor detected by the charge detector is completely discharged or the predetermined amount. A function for supplying electric power from a commercial AC power source to the hoisting / lowering motor via a power switch on condition that the following conditions are satisfied, and the frequency of the commercial AC power source from the start of the lowering operation by the inverter output during the lowering operation A function of performing an acceleration downwinding operation that accelerates at a predetermined acceleration until a high speed downwinding operation, a deceleration downwinding operation that decelerates at a predetermined deceleration from the high speed downwinding operation, and an In response to the synchronization completion signal from the inverter, the power supply of the hoisting and lowering motor is switched from the inverter to the commercial AC power supply. Switching function to switch the power of the vertical motor from the commercial AC power supply to the inverter. When the inverter reaches the frequency of the high-speed winding operation when the output frequency of the inverter reaches the frequency of the high-speed winding operation, the inverter supplies the output frequency to the commercial AC power supply. A function that outputs a synchronization completion signal to the control device when the inverter output and the commercial AC power supply are synchronized by the phase signal detected by the phase detector and the output phase signal of the inverter. When shifting from high-speed lowering operation to decelerating lowering operation, the output frequency is shifted by a predetermined amount from the frequency of the commercial AC power source , and the phase detector And a function of outputting a synchronization completion signal to the control device when the inverter output and the commercial AC power supply are synchronized with each other by the phase signal detected in step 1 and the output phase signal of the inverter.

The inverter as described above, the output frequency of the inverter is operated by shifting a predetermined amount than the frequency of the commercial AC power source the output frequency reaches the frequency at the time under high speed winding operation when under high speed winding operation, detected by the phase detector A function that outputs a synchronization completion signal to the control device when the inverter output and the commercial AC power supply are synchronized with each other by the phase signal and the output phase signal of the inverter, , its output frequency operated by shifting a predetermined amount than the frequency of the commercial AC power source, when the output phase signal of the phase signal and the inverter detected by the phase detector the inverter output and the commercial AC power supply is synchronized to the control unit And a function to output a synchronization completion signal, and the switching function of the control device allows the capacitor to be If there in a fully charged state, switches the power supply of the receiving synchronization completion signal winding vertical motion motor from the inverter from the inverter to a commercial AC power source. Further, when shifting from the high speed lowering operation to the deceleration lowering operation, the power source of the hoisting and lowering motor is switched from the commercial AC power source to the inverter in response to the synchronization completion signal from the inverter. Thereby, the regenerative electric power generated by the hoisting and lowering motor during the lowering operation can be used effectively without wasting it. Further, with a very simple configuration, when the hoisting / lowering motor is switched from the inverter output to the commercial AC power source and from the commercial AC power source to the inverter, the hoisting / lowering motor can be smoothly switched without giving an impact.

According to the present invention, while maintaining the function of slow stop, which is a feature of an inverter-driven hoisting machine, the regenerative power generated by the hoisting and lowering motor during the hoisting operation can be used almost without waste, and global warming can be prevented. to contribute to suppression, the power switching unit which can be inexpensively configured with easy single, winding up and down electric motor from the inverter to the commercial AC power source, the switching from the commercial AC power source to the inverter, is not to shock the winding up-and-down motor A hoisting machine can be provided.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a system configuration of a hoist according to the present invention. As shown in the figure, the hoisting machine includes a commercial AC power supply 10, an inverter 11, a hoisting and lowering motor (induction motor) 12, and a control device 13. Reference numeral 14 denotes an operation box, and the operation box 14 includes a winding push button switch 15 and a winding push button switch 16. The hoisting pushbutton switch 15 includes a first-stage switch 15a for low-speed hoisting and a second-stage switch 15b for high-speed hoisting. A stage switch 16a and a second stage switch 16b for high-speed winding are provided.

  By operating the first-stage switch 15a of the hoisting pushbutton switch 15 and the second-stage switch 15b, the signal is input to the control device 13, and the first-stage switch 16a of the lowering pushbutton switch 16; By operating the second-stage switch 16b, the signal is input to the control device 13. Reference numeral 17 denotes a phase detector that detects the voltage phase between the R phase and the S phase of the commercial AC power supply 10, and the phase detection signal S <b> 1 is input to the control device 13. Reference numerals 18 and 19 are electromagnetic switches for switching the power source. The electromagnetic switch 18 is an electromagnetic switch for connecting the hoisting and lowering motor 12 to the inverter 11 side via the contact 18a. The electromagnetic switch 19 is used for the hoisting and lowering motor 12. It is an electromagnetic switch connected to the commercial AC power supply 10 through the contact 19a.

  Reference numeral 23 denotes a capacitor for charging regenerative power generated by the hoisting / lowering motor 12 during the lowering operation, as will be described in detail later. The capacitor 23 is connected to a DC section (not shown) of the inverter 11 via a bidirectional chopper circuit 26 including transistors T1 and T2. A charge detector 27 detects the charge state of the capacitor 23, and a charge detection signal S 6 of the charge detector 27 is input to the control device 13. Control signals S7 and S8 for turning on and off the transistors T1 and T2 of the bidirectional chopper circuit 26 are output from the control device 13.

  Reference numeral 20 denotes a mechanical brake that restrains the hoisting and lowering motor 12. When a direct current from the diode stack 21 connected to the V phase of the output of the inverter 11 is energized, the brake 20 is opened and the contact 22 a of the electromagnetic switch 22 is opened. Is closed and the direct current to the brake 20 is interrupted, the brake 20 is activated and a braking force is applied. The electromagnetic switch 22 is controlled by the control device 13. Reference numeral 24 denotes an upper limit switch for stopping the hoisting operation when the load suspension hook (not shown) reaches the upper limit, and 25 is a lower limit switch for stopping the lowering operation when the load suspension hook reaches the lower limit. It is connected to the. The control device 13 outputs a forward (winding) command signal S2, a reverse (winding) command signal S3, and a high-speed command signal S4 to the inverter 11, and the inverter 11 outputs an inverter output described in detail later to the control device 13. A phase signal S5 indicating the phase of the signal is output.

  In the hoist having the above-described configuration, when the first-stage switch 15a for low-speed hoisting is closed by the operation of the hoisting pushbutton switch 15 of the operation box 14, the control device 13 determines that the hoisting signal is input, and the inverter 11 When the second-stage switch 15b for high-speed hoisting is closed, it is determined that a high-speed signal is input, and the high-speed command signal S4 is output to the inverter 11. When the first-stage switch 16a for low-speed lowering is closed by operating the push-down switch 16 for lowering, the control device 13 determines that the lowering signal is input, and sends a reverse (lowering) command signal S3 to the inverter 11. When the second-stage switch 16b for high-speed winding is closed, it is determined that a high-speed signal is input, and a high-speed command signal S4 is output to the inverter 11.

  By closing the first-stage switch 15a of the hoisting pushbutton switch 15, when the forward rotation (winding) command signal S2 is input to the inverter 11, the electric power in the forward rotation phase order is supplied from the inverter 11 to the hoisting and lowering motor 12. Is supplied, and the hoisting and lowering motor 12 is accelerated to a low hoisting operation speed at a predetermined acceleration. Here, by closing the second stage switch 15b, when the high-speed command signal S4 is input, the hoisting / lowering motor 12 is further accelerated to a high-speed hoisting operation speed at a commercial AC power source frequency at a predetermined acceleration. The second stage switch 15b that has reached the vicinity of the predetermined hoisting position at the high speed hoisting operation speed is opened to wind up to the predetermined hoisting position at the lower speed hoisting operation speed, and then the first stage switch 15a is opened to Stop at the hoisting position.

  When lowering from the predetermined hoisting position, the first-stage switch 16a of the lowering pushbutton switch 16 is closed so that when the reverse (lowering) command signal S3 is input to the inverter 11, the hoisting from the inverter 11 is performed. The electric power in the reverse phase order is supplied to the vertical motor 12, and the vertical motor 12 is accelerated at a predetermined acceleration to a low speed lowering operation speed. Here, by closing the second stage switch 16b, when the high speed command signal S4 is input, the hoisting / lowering motor 12 is further accelerated at a predetermined acceleration to a high speed lowering operation speed at the commercial AC power frequency. When it reaches the vicinity of the predetermined lowering position at the high speed lowering operation speed, the second stage switch 16b is opened, and the lowering operation is performed by lowering to the predetermined lowering position at the lower speed lowering operation speed. To do.

  The control device 13 monitors the charge state of the capacitor 23 based on the charge detection signal S6 from the charge detector 27. The control device 13 controls to turn on and off the transistors T1 and T2 of the bidirectional chopper circuit 26 when the capacitor 23 is in an uncharged state (a state where the capacitor 23 can be charged instead of a full charge) in the low speed winding operation and the high speed winding operation. Signals S <b> 7 and S <b> 8 are output, and the capacitor 23 is charged with the electric power generated by the hoisting and lowering motor 12 from the DC portion of the inverter 11. In addition, when the capacitor 23 is fully charged in the high-speed winding operation, the control device 13 transmits the regenerative power generated by the winding up / down motor 12 to the commercial AC power supply 10 by a method described in detail later. Further, the control device 13 turns the transistors T1 and T2 of the bidirectional chopper circuit 26 ON / OFF when the capacitor 23 is not completely discharged (with power to be discharged) in the low-speed hoisting operation and the high-speed hoisting operation. Control signals S7 and S8 are output, and the electric power charged in the capacitor 23 is supplied to the DC section of the inverter 11. As a result, while the capacitor 23 has charging power, the hoisting / lowering motor 12 is hoisted with the electric power via the inverter 11, and when there is no electric power to be discharged to the capacitor 23, the electric power from the commercial AC power supply 10 is used. Perform hoisting operation at.

  As described above, on the condition that the capacitor 23 is in an uncharged state (a state that can be charged instead of being fully charged) during the winding operation, the generated power of the hoisting / lowering motor 12 is charged into the capacitor 23, and during the winding operation, the capacitor Since the winding up / down motor 12 is operated with the electric power charged in the capacitor 23 until 23 is completely discharged, the regenerative power of the winding up / down motor 12 can be used without waste. The capacitor 23 is a capacitor having excellent charge / discharge capability, and for example, an electric double layer capacitor manufactured by Shizuki Electric Co., Ltd. is used.

  In addition, in preparation for an unexpected power failure, the charged power of the capacitor 23 is used as control power to safely unwind the package that has been wound up, that is, before the charged power of the capacitor 23 is completely discharged, that is, to the capacitor 23. The winding operation with the charging power of the capacitor 23 may be switched to the winding operation with the commercial AC power supply 10 in a state where a predetermined amount of charging power remains. The predetermined amount of charging power remaining in the capacitor 23 in this case refers to control power supplied to the control device 13 and the inverter 11 necessary for lowering the package being wound up.

  A predetermined amount of charging power remaining in the capacitor 23 is supplied as charging power for the capacitor 23 to the control device 13 and the inverter 11 via an emergency power supply circuit (not shown). Since the lowering operation is performed while charging the regenerative power to the capacitor 23, the predetermined amount of charging power remaining in the capacitor 23 can be minimized. In other words, by doing this, it is not necessary to prepare an emergency power supply in the event of a power failure, and the capacity of the capacitor 23 can be utilized to the maximum, so that the size of the device can be improved.

  Moreover, since the capacity | capacitance of the capacitor 23 is made to select suitably the capacity | capacitance for every winding machine according to the driving | running pattern (The generation | occurrence | production pattern of the electric power required for winding operation | movement, and the regenerative electric power collect | recovered by winding operation | movement) It becomes easy to reduce the size.

  As will be described later, the inverter 11 has a function of outputting a phase signal S5 indicating the phase of the output, and the phase signal S5 is input to the control device 13. In the above-described winding operation, when the forward rotation (winding) command signal S2 is input to the inverter 11 by closing the first-stage switch 15a of the winding pushbutton switch 15, the inverter 11 sends the signal to the winding up / down motor 12. The electric power in the forward rotation phase order is supplied, and the hoisting / lowering motor 12 is accelerated to a low hoisting operation speed at a predetermined acceleration. Here, by closing the second stage switch 15b, when the high-speed command signal S4 is input, the hoisting / lowering motor 12 is further accelerated to a high-speed hoisting operation speed at a commercial AC power source frequency at a predetermined acceleration. The second stage switch 15b that has reached the vicinity of the predetermined hoisting position at the high speed hoisting operation speed is opened to wind up to the predetermined hoisting position at the lower speed hoisting operation speed, and then the first stage switch 15a is opened to Stop at the hoisting position. In this low-speed hoisting operation and high-speed hoisting operation, when the capacitor 23 is not completely discharged, the control device 13 sends control signals S7 and S8 for turning on and off the transistors T1 and T2 of the bidirectional chopper circuit 26. Then, the electric power charged in the capacitor 23 is supplied to the DC part of the inverter 11. When the capacitor 23 is completely discharged, power from the commercial AC power supply 10 is supplied to the inverter 11.

  By closing the first-stage switch 16a of the lowering push button switch 16, when the reverse rotation (lowering) command signal S3 is input to the inverter 11, the electric power in the reverse phase order is supplied from the inverter 11 to the lower and upper motor 12. When the hoisting / lowering motor 12 is in the low speed lowering operation and the second stage switch 16b is closed, the lowering operation speed is reached. The eye switch 16b is opened and lowered to a predetermined lowering position at a low speed lowering operation speed. Here, the first stage switch 16a is opened to stop. In the low-speed winding operation and the high-speed winding operation, when the capacitor 23 is in an uncharged state, the control device 13 sends control signals S7 and S8 to the transistors T1 and T2 of the bidirectional chopper circuit 26 for winding up and down. The electric power generated by the electric motor 12 is charged into the capacitor 23 from the DC part of the inverter 11.

  Further, when the capacitor 23 cannot be charged in the fully charged state, the second-stage switch 16b of the lowering pushbutton switch 16 is closed, and when the high speed lowering operation speed is reached, the inverter 11 has an output frequency of the commercial AC power supply 10. The operation is performed by shifting a predetermined amount (for example, a frequency difference of 2 Hz) from the frequency. The controller 13 controls the electromagnetic switch 18 at the moment when the phase of the commercial AC power supply 10 and the phase of the output of the inverter 11 are synchronized by the phase signal S5 from the inverter 11 and the phase detection signal S1 detected by the phase detector 17. The contact 18a is opened as a non-operation, and the contact 19a is closed using the electromagnetic switch 19 as an operation. As a result, the power source of the hoisting and lowering motor 12 is switched from the inverter 11 to the commercial AC power source 10. In this way, the output frequency of the inverter 11 is shifted from the frequency of the commercial AC power supply 10 by a predetermined amount, and the inverter 11 and the commercial AC power supply 10 are synchronized with each other to switch from the inverter 11 to the commercial AC power supply 10 at the same time. At the time of this switching, no impact is applied to the winding up / down motor 12.

  When switching to the commercial AC power source 10 and reaching the vicinity of a predetermined lowering position, the second-stage switch 16b is opened, whereby the high-speed command signal S4 from the control device 13 is cut off and becomes the reverse (lowering) command signal S3. As a result, the inverter 11 is operated with its output frequency shifted from the frequency of the commercial AC power supply 10 by a predetermined amount (for example, a frequency difference of 2 Hz). The control device 13 then detects the electromagnetic switch 18 at the moment when the phase of the commercial AC power supply 10 and the phase of the output of the inverter 11 are synchronized by the phase signal S5 from the inverter 11 and the phase detection signal S1 detected by the phase detector 17. And the electromagnetic switch 19 is deactivated. Thereby, the contact 18a of the electromagnetic switch 18 is closed, the contact 19a of the electromagnetic switch 19 is opened, and the power supply of the hoisting and lowering motor 12 is switched from the commercial AC power supply 10 to the output of the inverter 11. Thereby, an impact is not given to the winding up / down motor 12 at the time of switching.

  FIG. 2 is a diagram showing the switching timing at the time of the lowering operation. When the first-stage switch 16a of the lowering pushbutton switch 16 is turned on at time t1, a reverse rotation command signal S3 is output, accelerated at a predetermined acceleration, and reaches a lower lowering speed at time t2. When the second-stage switch 16b of the lowering push button switch 16 is turned on at time t3, a high speed command signal S4 is output, accelerated at a predetermined acceleration, and reaches the high speed lowering operation speed at time t4. The output frequency of the inverter 11 is reduced by a predetermined amount from time t8 by turning off the second-stage switch 16b of the push-down push button switch 16 at time t6 when it reaches the vicinity of the predetermined position for lowering at the high speed lowering operation speed. Decrease with speed, and reach low speed downwinding deceleration at time t9. At time t10 when the predetermined lowering position is reached, the first-stage switch 16a of the lowering pushbutton switch 16 is turned off to stop the reverse rotation instruction signal S3 and stop the lowering motor 12 for lowering.

  In the lowering operation from time t1 to time t11, when the capacitor 23 is not fully charged but can be charged, the electric power generated by the hoisting and lowering motor 12 is charged in the capacitor 23. Further, when the capacitor 23 is in a fully charged state and is operated at a high winding speed (time t5 to time t7), the output frequency of the inverter 11 is set to a predetermined amount from the frequency of the commercial AC power supply 10. The power of the hoisting and lowering motor 12 is turned on when the commercial AC power supply 10 and the output of the inverter 11 are synchronized with each other by the phase signal S5 from the inverter 11 and the phase detection signal S1 detected by the phase detector 17. Switching from the output of the inverter 11 to the commercial AC power supply 10 (contact 18a of the electromagnetic switch 18 is turned OFF and contact 19a of the electromagnetic switch 19 is turned ON), and the hoisting and lowering motor 12 is wound down at the AC power frequency to generate power The regenerative power to be returned is returned to the commercial AC power source 10. At time t6, the inverter 11 is operated with its output frequency shifted by a predetermined amount from the frequency of the commercial AC power supply 10, and the phase signal S5 from the inverter 11 and the phase detection signal S1 detected by the phase detector 17 At time t7 when the outputs of the commercial AC power supply 10 and the inverter 11 are synchronized, the power supply of the hoisting and lowering motor 12 is switched from the commercial AC power supply 10 to the output of the inverter 11 (the contact 19a of the electromagnetic switch 19 is turned off, the electromagnetic switch 18 The contact 18a is turned ON), and the winding operation is performed by the output of the inverter 11.

  In the hoisting machine, by appropriately setting the capacity of the capacitor 23, it is possible to eliminate the need for a regenerative braking resistor. In addition, although illustration is abbreviate | omitted, when a small capacity | capacitance regenerative resistor is provided and the capacitor 23 cannot be charged in a fully charged state, from the start of the lowering operation during the lowering operation to the high speed lowering operation ( Winding up / down motor 12 between time t1 to t5 in FIG. 2 and from the high speed lowering operation to stop of switching hoisting motor 12 to inverter 11 (between time t7 to time t11 in FIG. 2). The electric power generated by may be consumed by the regenerative resistor. In this case, the electric power (energy) consumed by the regenerative resistor is a portion indicated by hatching in FIG. 2 and the capacitor 23 cannot be charged in a fully charged state, so that a resistor having a small capacity is sufficient.

  FIG. 3 is a diagram illustrating a waveform example of the phase signal S5 indicating the phase of the U-phase output of the inverter 11 and the phase of the inverter output output from the inverter 11. As shown in the drawing, a phase signal S5 indicating the phase of the U-phase output as shown in (b) is output with respect to the waveform of the U-phase output of the inverter 11 shown in (a). Outputting such a phase signal S5 is because the inverter 11 is a frequency conversion device, so that it is output to the outside as phase information of the output voltage that it produces, and it is easy as an inverter function (ancillary function of the inverter). It is. The control device 13 compares the phase signal S5 from the inverter 11 with the phase detection signal S1 of the commercial AC power supply 10 detected by the phase detector 17, and when both coincide with each other (when synchronized), the winding up / down motor 12 Is switched from the output of the inverter 11 to the commercial AC power supply 10 or from the commercial AC power supply 10 to the output of the inverter 11.

  FIG. 4 shows the voltage waveform of the commercial AC power supply R phase and the voltage waveforms of the U, V, and W phases of the inverter when the power of the hoisting and lowering motor 12 during the lowering operation is switched from the output of the inverter 11 to the commercial AC power supply 10. FIG. 3 is a diagram showing an example of a load current waveform. Here, the frequency difference between the commercial AC power source frequency and the inverter 11 is set to 2 Hz, and the output from the inverter 11 is switched to the commercial AC power source 10 at the moment when both power sources are synchronized. Switching time (time when the hoisting / lowering motor 12 is not connected to either the inverter 11 or the commercial AC power supply 10) ΔT≈12.8 ms, and switching can be performed without giving an impact to the hoisting / lowering motor 12. confirmed.

  FIG. 5 shows the voltage waveform of the commercial AC power supply R phase and the voltage waveforms of the U, V, and W phases of the inverter when the power source of the hoisting and lowering motor 12 during the lowering operation is switched from the commercial AC power supply 10 to the output of the inverter 11. FIG. 3 is a diagram showing an example of a load current waveform. Here, the frequency difference between the commercial AC power supply frequency and the inverter 11 is set to 2 Hz, and the commercial AC power supply 10 is switched to the output of the inverter 11 at the moment when both power supplies are synchronized. It was confirmed that switching can be performed without giving an impact to the hoisting / lowering motor 12 with a switching time ΔT≈13.8 ms.

FIG. 6 is a diagram showing a synchronization point periodic table of 50 Hz system and 60 Hz system. The figure shows the time difference (waveform deviation time) after one cycle when the A system frequency is X and the B system frequency Y is started from the synchronization point in both the A system and the B system.
(1 / X)-(1 / Y) = T ₁
From this time difference T ₁ , the time until the synchronization point is reached again (synchronization point cycle) T ₂
T ₂ = {(1 / X) / T ₁ } × (1 / X)
Is a table showing a synchronization point periodic table calculated as The greater the frequency difference between the A and B systems, the shorter the period of the synchronization point. When the frequency difference between the A system and the B system is 2 Hz at the maximum, the frequency difference is ± 2 Hz under the detection condition of the phase detector 17, so the period of the synchronization point is 0.52 (sec). Since this is a case where the power source is in an ideal state, the time T ₂ may become longer due to voltage and frequency fluctuations during detection.

  FIG. 7 is a diagram showing another system configuration of the hoist according to the present invention. In the figure, the parts denoted by the same reference numerals as those in FIG. When the capacitor 23 is fully charged during the lowering operation and the power generated by the hoisting / lowering motor 12 cannot be charged to the capacitor 23, the power needs to be transmitted to the commercial AC power supply 10. In this case, here, the phase detection signal S 1 of the commercial AC power supply 10 detected by the phase detector 17 is sent to the inverter 11, and the inverter 11 is operated so as to synchronize the phase of the output with the phase of the commercial AC power supply 10. When the synchronization is completed, the inverter 11 outputs a synchronization completion signal S9 to the control device 13. Upon receiving this synchronization completion signal, the control device 13 opens the contact 18a of the electromagnetic switch 18, closes the contact 19a of the electromagnetic switch 19, and switches the power of the hoisting and lowering motor 12 from the inverter 11 to the commercial AC power supply 10. It is like that.

  When the capacitor 23 is in a fully charged state during the lowering operation as described above, and the power generated by the hoisting and lowering motor 12 cannot be charged in the capacitor 23, the output of the inverter 11 is synchronized with the phase of the commercial AC power supply 10, When the synchronization is completed, the contact 18a of the electromagnetic switch 18 is opened and the contact 19a of the electromagnetic switch 19 is closed, so that the power of the winding up / down motor 12 is supplied to the inverter 11 without impacting the winding up / down motor 12. Can be switched to the commercial AC power source 10. Since the inverter is a frequency converter, outputting such a synchronization completion signal S9 also means that the phase of the output voltage created by itself is synchronized with the phase of the voltage of another system, and the synchronization completion signal S9 is output simultaneously with the completion of synchronization. This is also easy as an inverter function (ancillary function of the inverter). As described above, the inverter 10 receives the phase detection signal S1 of the commercial AC power supply 10 from the phase detector 17, synchronizes the output phase with the commercial AC power supply 10, and outputs the synchronization completion signal S9 to the control device 13. The regenerative power generated by the hoisting / lowering motor 12 during high-speed winding operation with the commercial AC power supply 10 can be returned to the commercial AC power supply 10 simply by providing the commercial AC power supply 10.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. Note that any shape or material not directly described in the specification and drawings is within the scope of the technical idea of the present invention as long as the effects and advantages of the present invention are achieved. For example, in the embodiment described above, a two-speed hoist is described as an example, but the present invention can also be applied to a one-speed hoist.

It is a figure which shows the system structural example of the winding machine which concerns on this invention. It is a figure which shows the switching timing at the time of the winding operation of the winding machine which concerns on this invention. It is a figure which shows the phase signal output from the inverter at the time of the winding operation of the winding machine which concerns on this invention. It is a figure which shows the waveform at the time of switching the power supply at the time of the winding operation of the winding machine which concerns on this invention from an inverter to commercial AC power supply. It is a figure which shows the waveform at the time of switching the power supply at the time of the winding operation of the winding machine which concerns on this invention from a commercial AC power supply to an inverter. It is a figure which shows the synchronization point periodic table of 50Hz type | system | group and 60Hz type | system | group. It is a figure which shows the other system configuration example of the winding machine which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Commercial AC power supply 11 Inverter 12 Winding up / down motor 13 Control device 14 Operation box 15 Hoisting pushbutton switch 16 Lowering pushbutton switch 17 Phase detector 18 Electromagnetic switch 19 Electromagnetic switch 20 Brake 21 Diode stack 22 Electromagnetic Switch 23 Capacitor 24 Upper limit switch 25 Lower limit switch 26 Bidirectional chopper circuit 27 Charge detector

Claims (2)

In a hoisting machine having a commercial AC power source, an inverter, a hoisting and lowering motor, and a control device, controlling the inverter by the control of the control device, starting the hoisting and lowering motor and performing a hoisting and lowering operation,
A capacitor, a power switch, a charge detector, and a phase detector for detecting the phase of the commercial AC power supply;
The inverter has a function of outputting a phase signal indicating the phase of the output,
The control device connects the winding up / down motor to the inverter via the power switch on the condition that the charge detector detects uncharged of the capacitor during the winding operation. The electric power generated by the up / down motor is charged in the capacitor, and the commercial AC is connected to the winding up / down motor through the power switch on condition that the charge detector detects the full charge of the capacitor. Connected to a power source, the power generated by the hoisting and lowering motor is transmitted to the commercial AC power source, and the charging power of the capacitor detected by the charge detector during hoisting operation is not completely discharged or less than a predetermined amount The power charged in the capacitor is supplied to the winding up / down motor through the inverter on the condition that the charging power of the capacitor detected by the charge detector is Power and a function of supplying to the winding up-and-down motor from the commercial AC power source through the power switching device on condition that it is a discharge or a predetermined amount or less,
During the lowering operation, the inverter output is used to perform an acceleration lowering operation that accelerates at a predetermined acceleration from the start of the lowering operation to a high-speed lowering operation at the frequency of the commercial AC power supply , and a deceleration that decelerates from the high-speed lowering operation at a predetermined deceleration. The function of performing the lowering operation, and when the output frequency of the inverter reaches the frequency during the high speed lowering operation during the high speed lowering operation , the inverter is operated by shifting the output frequency by a predetermined amount from the frequency of the commercial AC power supply. When the inverter output and the commercial AC power supply are synchronized by the phase signal detected by the phase detector and the phase signal from the inverter, the winding up / down motor is connected to the inverter via the power switch. When switching from the commercial AC power source to the commercial AC power source and shifting from the high speed lowering operation to the deceleration lowering operation, the output frequency of the inverter is high speed The output frequency of the inverter reaches the frequency at the time of rolling is operated by shifting a predetermined amount than the frequency of the commercial AC power supply, the phase signal from the phase signal detected by the phase detector and the inverter, the inverter output When the commercial AC power source is synchronized with the commercial AC power source, a switching function for switching the power source of the hoisting and lowering motor from the commercial AC power source to the inverter via the power source switching unit,
A hoisting machine characterized by comprising: In a hoisting machine having a commercial AC power source, an inverter, a hoisting and lowering motor, and a control device, controlling the inverter by the control of the control device, starting the hoisting and lowering motor and performing a hoisting and lowering operation,
A capacitor, a power switch, a charge detector, and a phase detector for detecting the phase of the commercial AC power supply;
The inverter receives a phase signal detected by the phase detector, synchronizes its output with the commercial AC power supply, and has a function of outputting a synchronization completion signal to the control device when synchronization is completed,
The control device connects the winding up / down motor to the inverter via the power switch on the condition that the charge detector detects uncharged of the capacitor during the winding operation. The electric power generated by the up / down motor is charged in the capacitor, and the commercial AC is connected to the winding up / down motor through the power switch on condition that the charge detector detects the full charge of the capacitor. Connected to a power source, the power generated by the hoisting and lowering motor is transmitted to the commercial AC power source, and the charging power of the capacitor detected by the charge detector during hoisting operation is not completely discharged or less than a predetermined amount The power charged in the capacitor is supplied to the winding up / down motor through the inverter on the condition that the charging power of the capacitor detected by the charge detector is Power and a function of supplying to the winding up-and-down motor from the commercial AC power source through the power switching device on condition that it is a discharge or a predetermined amount or less,
During the lowering operation, the inverter output is used to perform an acceleration lowering operation that accelerates at a predetermined acceleration from the start of the lowering operation to a high-speed lowering operation at the frequency of the commercial AC power supply , and a deceleration that decelerates from the high-speed lowering operation at a predetermined deceleration. The function of performing the lowering operation and the synchronization completion signal from the inverter at the time of the high speed lowering operation, the power of the hoisting and lowering motor is switched from the inverter to the commercial AC power source, and the deceleration from the high speed lowering operation When shifting to the unwinding operation, a switching function for receiving a synchronization completion signal from the inverter and switching the power source of the hoisting and lowering motor from the commercial AC power source to the inverter,
The inverter is operated by shifting the output frequency by a predetermined amount from the frequency of the commercial AC power source when the output frequency of the inverter reaches the frequency during high-speed winding operation during the high-speed winding operation, and is detected by the phase detector. A function of outputting the synchronization completion signal to the control device when the inverter output and the commercial AC power supply are synchronized with each other by the phase signal and the output phase signal of the inverter; When shifting to the lower operation, the output frequency is shifted by a predetermined amount from the frequency of the commercial AC power supply , and the inverter output and the phase signal detected by the phase detector and the output phase signal of the inverter A function of outputting the synchronization completion signal to the control device when the commercial AC power supply is synchronized;
A hoisting machine characterized by comprising:

Images